On 11/8/2022 12:52 AM, Ville Syrjälä wrote:
On Mon, Nov 07, 2022 at 07:34:43PM -0800, Rob Clark wrote:
On Mon, Nov 7, 2022 at 4:22 PM Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>wrote:
On 11/7/2022 2:09 PM, Rob Clark wrote:
On Mon, Nov 7, 2022 at 1:32 PM Jessica Zhang <quic_jesszhan@xxxxxxxxxxx> wrote:
On 11/7/2022 11:37 AM, Ville Syrjälä wrote:
On Fri, Oct 28, 2022 at 03:59:49PM -0700, Jessica Zhang wrote:
Introduce and add support for COLOR_FILL and COLOR_FILL_FORMAT
properties. When the color fill value is set, and the framebuffer is set
to NULL, memory fetch will be disabled.
Thinking a bit more universally I wonder if there should be
some kind of enum property:
enum plane_pixel_source {
FB,
COLOR,
LIVE_FOO,
LIVE_BAR,
...
}
Hi Ville,
Makes sense -- this way, we'd also lay some groundwork for cases where
drivers want to use other non-FB sources.
In addition, loosen the NULL FB checks within the atomic commit callstack
to allow a NULL FB when color_fill is nonzero and add FB checks in
methods where the FB was previously assumed to be non-NULL.
Finally, have the DPU driver use drm_plane_state.color_fill and
drm_plane_state.color_fill_format instead of dpu_plane_state.color_fill,
and add extra checks in the DPU atomic commit callstack to account for a
NULL FB in cases where color_fill is set.
Some drivers support hardware that have optimizations for solid fill
planes. This series aims to expose these capabilities to userspace as
some compositors have a solid fill flag (ex. SOLID_COLOR in the Android
hardware composer HAL) that can be set by apps like the Android Gears
app.
Userspace can set the color_fill value by setting COLOR_FILL_FORMATto a
DRM format, setting COLOR_FILL to a color fill value, and setting the
framebuffer to NULL.
Is there some real reason for the format property? Ie. why not
just do what was the plan for the crttc background color and
specify the color in full 16bpc format and just pick as many
msbs from that as the hw can use?
The format property was added because we can't assume that all hardware
will support/use the same color format for solid fill planes. Even for
just MSM devices, the hardware supports different variations of RGB
formats [1].
Sure, but the driver can convert the format into whatever the hw
wants. A 1x1 color conversion is not going to be problematic ;-)
Hi Rob,
Hm... that's also a fair point. Just wondering, is there any advantage
of having the driver convert the format, other than not having to
implement an extra format property?
(In case we end up wrapping everything into a prop blob or something)
It keeps the uabi simpler.. for obvious reasons you don't want the
driver to do cpu color conversion for an arbitrary size plane, which
is why we go to all the complexity to expose formats and modifiers for
"real" planes, but we are dealing with a single pixel value here,
let's not make the uabi more complex than we need to. I'd propose
making it float32[4] if float weren't a pita for kernel/uabi, but
u16[4] or u32[4] should be fine, and drivers can translate that easily
into whatever weird formats their hw wants for solid-fill.
u16[4] fits into a single u64 property value.
That was the plan for the background prop as well:
https://lore.kernel.org/all/20190703125442.GW5942@xxxxxxxxx/T/
Got it, I think that's pretty reasonable then. Will probably use u32[4]
instead since that is what Pekka and Simon are recommending to match
Wayland's single-buffer protocol [1].
Thanks,
Jessica Zhang
[1]
https://gitlab.freedesktop.org/wayland/wayland-protocols/-/merge_requests/104
--
Ville Syrjälä
Intel
